<template>
    <div class="list" ref="wrapper">
        <div>
            <div class="area">
            <div class="title border-topbottom">当前城市</div>
            <div class="button-list">
                <div class="button-wrapper">
                    <div class="button">{{this.currentCity}}</div>
                </div>
            </div>
        </div>
        <div class="area">
            <div class="title border-topbottom">热门城市</div>
            <div class="button-list">
                <div class="button-wrapper" 
                 v-for="hotCity in hot" 
                :key="hotCity.id"
                @click="hanleCityClick(hotCity.name)">
                    <div class="button">{{hotCity.name}}</div>
                </div>
            </div>
        </div>
        <div class="area" 
        v-for="(item,key) of cities" 
        :key="key"
        :ref="key">
            <div class="title border-topbottom">{{key}}</div>
            <div class="item-list">
                <div class="item border-bottom" 
                v-for="city of item" 
                :key="city.id"
                @click="hanleCityClick(city.name)"
                >{{city.name}}</div>
            </div>
        </div>
        </div>
    </div>
</template>
<script>
import {mapState,mapMutations} from 'vuex'
import Bscroll from 'better-scroll'
export default {
    name:'CityList',
    props:{
        cities:Object,
        hot:Array,
        letter:String
    },
    computed:{
         ...mapState({
             currentCity:'city'
         })
    },
    watch:{
        letter () {
            if(this.letter){
                const element = this.$refs[this.letter][0]
                this.scroll.scrollToElement(element)
            }
            // console.log(this.letter)
        }
    },methods:{
        hanleCityClick(city){
            // 改变city的时候 使用dispatch
            // this.$store.commit('changeCity',city);  与下一句等价
            this.changeCity(city)
            this.$router.push('/')
        },
        ...mapMutations(['changeCity'])
    },
    mounted () {
        this.scroll = new Bscroll(this.$refs.wrapper)
    }
}
</script>
<style lang="stylus" scoped>
    @import "~styles/varibales.styl"; 
    .border-topbottom
        &:before
            border-color:#ccc
        &:after
            border-color:#ccc
    .border-topbottom
        &:before
            border-color:#ccc
    .list
        overflow:hidden
        position:absolute
        top:1.58rem
        left:0
        right :0
        bottom :0
        .title
            line-height :.54rem
            background :#eee
            padding-left :.2rem
            color:#666
            font-size :.26rem
        .button-list
            overflow:hidden //触发BFC
            padding :.1rem .6rem .1rem .1rem
            .button-wrapper
                float :left
                width :33.33%
                .button
                    margin : .1rem
                    padding :.1rem 0
                    text-align :center
                    border :.02rem solid #ccc
                    border-radius:.06rem
        .item-list
            .item
                line-height :.76rem
                color :#666
                padding-left :.2rem
</style>